Use Assert.state() where appropriate

spring-beans/src/main/java/org/springframework/beans/factory/serviceloader/AbstractServiceLoaderBasedFactoryBean.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2017 the original author or authors.
+ * Copyright 2002-2022 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -69,7 +69,7 @@ public void setBeanClassLoader(@Nullable ClassLoader beanClassLoader) {
 	 */
 	@Override
 	protected Object createInstance() {
-		Assert.notNull(getServiceType(), "Property 'serviceType' is required");
+		Assert.state(getServiceType() != null, "Property 'serviceType' is required");
 		return getObjectToExpose(ServiceLoader.load(getServiceType(), this.beanClassLoader));
 	}
 

spring-context-support/src/main/java/org/springframework/cache/jcache/interceptor/DefaultJCacheOperationSource.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2022 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -166,7 +166,7 @@ public void setBeanFactory(BeanFactory beanFactory) {
 	public void afterSingletonsInstantiated() {
 		// Make sure that the cache resolver is initialized. An exception cache resolver is only
 		// required if the exceptionCacheName attribute is set on an operation.
-		Assert.notNull(getDefaultCacheResolver(), "Cache resolver should have been initialized");
+		Assert.state(getDefaultCacheResolver() != null, "Cache resolver should have been initialized");
 	}
 
 

spring-context/src/main/java/org/springframework/scheduling/annotation/ProxyAsyncConfiguration.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2020 the original author or authors.
+ * Copyright 2002-2022 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -44,7 +44,7 @@ public class ProxyAsyncConfiguration extends AbstractAsyncConfiguration {
 	@Bean(name = TaskManagementConfigUtils.ASYNC_ANNOTATION_PROCESSOR_BEAN_NAME)
 	@Role(BeanDefinition.ROLE_INFRASTRUCTURE)
 	public AsyncAnnotationBeanPostProcessor asyncAdvisor() {
-		Assert.notNull(this.enableAsync, "@EnableAsync annotation metadata was not injected");
+		Assert.state(this.enableAsync != null, "@EnableAsync annotation metadata was not injected");
 		AsyncAnnotationBeanPostProcessor bpp = new AsyncAnnotationBeanPostProcessor();
 		bpp.configure(this.executor, this.exceptionHandler);
 		Class<? extends Annotation> customAsyncAnnotation = this.enableAsync.getClass("annotation");

spring-context/src/main/java/org/springframework/validation/beanvalidation/LocalValidatorFactoryBean.java

@@ -378,43 +378,43 @@ protected void postProcessConfiguration(Configuration<?> configuration) {
 
 	@Override
 	public Validator getValidator() {
-		Assert.notNull(this.validatorFactory, "No target ValidatorFactory set");
+		Assert.state(this.validatorFactory != null, "No target ValidatorFactory set");
 		return this.validatorFactory.getValidator();
 	}
 
 	@Override
 	public ValidatorContext usingContext() {
-		Assert.notNull(this.validatorFactory, "No target ValidatorFactory set");
+		Assert.state(this.validatorFactory != null, "No target ValidatorFactory set");
 		return this.validatorFactory.usingContext();
 	}
 
 	@Override
 	public MessageInterpolator getMessageInterpolator() {
-		Assert.notNull(this.validatorFactory, "No target ValidatorFactory set");
+		Assert.state(this.validatorFactory != null, "No target ValidatorFactory set");
 		return this.validatorFactory.getMessageInterpolator();
 	}
 
 	@Override
 	public TraversableResolver getTraversableResolver() {
-		Assert.notNull(this.validatorFactory, "No target ValidatorFactory set");
+		Assert.state(this.validatorFactory != null, "No target ValidatorFactory set");
 		return this.validatorFactory.getTraversableResolver();
 	}
 
 	@Override
 	public ConstraintValidatorFactory getConstraintValidatorFactory() {
-		Assert.notNull(this.validatorFactory, "No target ValidatorFactory set");
+		Assert.state(this.validatorFactory != null, "No target ValidatorFactory set");
 		return this.validatorFactory.getConstraintValidatorFactory();
 	}
 
 	@Override
 	public ParameterNameProvider getParameterNameProvider() {
-		Assert.notNull(this.validatorFactory, "No target ValidatorFactory set");
+		Assert.state(this.validatorFactory != null, "No target ValidatorFactory set");
 		return this.validatorFactory.getParameterNameProvider();
 	}
 
 	@Override
 	public ClockProvider getClockProvider() {
-		Assert.notNull(this.validatorFactory, "No target ValidatorFactory set");
+		Assert.state(this.validatorFactory != null, "No target ValidatorFactory set");
 		return this.validatorFactory.getClockProvider();
 	}
 

spring-core-test/src/main/java/org/springframework/aot/agent/RecordedInvocation.java

@@ -98,7 +98,7 @@ public Stream<StackWalker.StackFrame> getStackFrames() {
 	 */
 	@SuppressWarnings("unchecked")
 	public <T> T getInstance() {
-		Assert.notNull(this.instance, "Cannot resolve 'this' for static invocations");
+		Assert.state(this.instance != null, "Cannot resolve 'this' for static invocations");
 		return (T) this.instance;
 	}
 
@@ -108,7 +108,7 @@ public <T> T getInstance() {
 	 * @throws IllegalStateException in case of static invocations (there is no {@code this})
 	 */
 	public TypeReference getInstanceTypeReference() {
-		Assert.notNull(this.instance, "Cannot resolve 'this' for static invocations");
+		Assert.state(this.instance != null, "Cannot resolve 'this' for static invocations");
 		return TypeReference.of(this.instance.getClass());
 	}
 

spring-core-test/src/main/java/org/springframework/aot/test/agent/RuntimeHintsRecorder.java

@@ -49,7 +49,7 @@ private RuntimeHintsRecorder() {
 	 */
 	public synchronized static RuntimeHintsInvocations record(Runnable action) {
 		Assert.notNull(action, "Runnable action must not be null");
-		Assert.isTrue(RuntimeHintsAgent.isLoaded(), "RuntimeHintsAgent should be loaded in the current JVM");
+		Assert.state(RuntimeHintsAgent.isLoaded(), "RuntimeHintsAgent must be loaded in the current JVM");
 		RuntimeHintsRecorder recorder = new RuntimeHintsRecorder();
 		RecordedInvocationsPublisher.addListener(recorder.listener);
 		try {

spring-core-test/src/test/java/org/springframework/aot/agent/RecordedInvocationTests.java

@@ -63,8 +63,8 @@ void buildValidStaticInvocation() {
 
 	@Test
 	void staticInvocationShouldThrowWhenGetInstance() {
-		assertThatThrownBy(staticInvocation::getInstance).isInstanceOf(IllegalArgumentException.class);
-		assertThatThrownBy(staticInvocation::getInstanceTypeReference).isInstanceOf(IllegalArgumentException.class);
+		assertThatThrownBy(staticInvocation::getInstance).isInstanceOf(IllegalStateException.class);
+		assertThatThrownBy(staticInvocation::getInstanceTypeReference).isInstanceOf(IllegalStateException.class);
 	}
 
 	@Test

spring-core/src/main/java/org/springframework/aot/generate/DefaultMethodReference.java

@@ -42,29 +42,32 @@ public class DefaultMethodReference implements MethodReference {
 	@Nullable
 	private final ClassName declaringClass;
 
+
 	public DefaultMethodReference(MethodSpec method, @Nullable ClassName declaringClass) {
 		this.method = method;
 		this.declaringClass = declaringClass;
 	}
 
+
 	@Override
 	public CodeBlock toCodeBlock() {
 		String methodName = this.method.name;
 		if (isStatic()) {
-			Assert.notNull(this.declaringClass, "static method reference must define a declaring class");
+			Assert.state(this.declaringClass != null, "static method reference must define a declaring class");
 			return CodeBlock.of("$T::$L", this.declaringClass, methodName);
 		}
 		else {
 			return CodeBlock.of("this::$L", methodName);
 		}
 	}
 
+	@Override
 	public CodeBlock toInvokeCodeBlock(ArgumentCodeGenerator argumentCodeGenerator,
 			@Nullable ClassName targetClassName) {
 		String methodName = this.method.name;
 		CodeBlock.Builder code = CodeBlock.builder();
 		if (isStatic()) {
-			Assert.notNull(this.declaringClass, "static method reference must define a declaring class");
+			Assert.state(this.declaringClass != null, "static method reference must define a declaring class");
 			if (isSameDeclaringClass(targetClassName)) {
 				code.add("$L", methodName);
 			}

spring-core/src/test/java/org/springframework/aot/generate/DefaultMethodReferenceTests.java

@@ -30,6 +30,7 @@
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
+import static org.assertj.core.api.Assertions.assertThatIllegalStateException;
 
 /**
  * Tests for {@link DefaultMethodReference}.
@@ -86,7 +87,7 @@ void toCodeBlockWithStaticMethod() {
 	void toCodeBlockWithStaticMethodRequiresDeclaringClass() {
 		MethodSpec method = createTestMethod("methodName", new TypeName[0], Modifier.STATIC);
 		MethodReference methodReference = new DefaultMethodReference(method, null);
-		assertThatIllegalArgumentException().isThrownBy(methodReference::toCodeBlock)
+		assertThatIllegalStateException().isThrownBy(methodReference::toCodeBlock)
 				.withMessage("static method reference must define a declaring class");
 	}
 

spring-jdbc/src/main/java/org/springframework/jdbc/datasource/ConnectionHolder.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2022 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -157,7 +157,7 @@ protected void setConnection(@Nullable Connection connection) {
 	 * @see #released()
 	 */
 	public Connection getConnection() {
-		Assert.notNull(this.connectionHandle, "Active Connection is required");
+		Assert.state(this.connectionHandle != null, "Active Connection is required");
 		if (this.currentConnection == null) {
 			this.currentConnection = this.connectionHandle.getConnection();
 		}

spring-jdbc/src/main/java/org/springframework/jdbc/datasource/SimpleDriverDataSource.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2020 the original author or authors.
+ * Copyright 2002-2022 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -136,8 +136,8 @@ public Driver getDriver() {
 	@Override
 	protected Connection getConnectionFromDriver(Properties props) throws SQLException {
 		Driver driver = getDriver();
+		Assert.state(driver != null, "Driver has not been set");
 		String url = getUrl();
-		Assert.notNull(driver, "Driver must not be null");
 		if (logger.isDebugEnabled()) {
 			logger.debug("Creating new JDBC Driver Connection to [" + url + "]");
 		}

spring-messaging/src/main/java/org/springframework/messaging/converter/MarshallingMessageConverter.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2020 the original author or authors.
+ * Copyright 2002-2022 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -144,7 +144,7 @@ protected boolean supports(Class<?> clazz) {
 	@Override
 	@Nullable
 	protected Object convertFromInternal(Message<?> message, Class<?> targetClass, @Nullable Object conversionHint) {
-		Assert.notNull(this.unmarshaller, "Property 'unmarshaller' is required");
+		Assert.state(this.unmarshaller != null, "Property 'unmarshaller' is required");
 		try {
 			Source source = getSource(message.getPayload());
 			Object result = this.unmarshaller.unmarshal(source);
@@ -172,7 +172,7 @@ private Source getSource(Object payload) {
 	protected Object convertToInternal(Object payload, @Nullable MessageHeaders headers,
 			@Nullable Object conversionHint) {
 
-		Assert.notNull(this.marshaller, "Property 'marshaller' is required");
+		Assert.state(this.marshaller != null, "Property 'marshaller' is required");
 		try {
 			if (byte[].class == getSerializedPayloadClass()) {
 				ByteArrayOutputStream out = new ByteArrayOutputStream(1024);

spring-r2dbc/src/main/java/org/springframework/r2dbc/connection/ConnectionHolder.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2020 the original author or authors.
+ * Copyright 2002-2022 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -23,7 +23,6 @@
 import org.springframework.transaction.support.ResourceHolderSupport;
 import org.springframework.util.Assert;
 
-
 /**
  * Resource holder wrapping a R2DBC {@link Connection}.
  * {@link R2dbcTransactionManager} binds instances of this class to the subscription,
@@ -109,7 +108,7 @@ protected void setConnection(@Nullable Connection connection) {
 	 * @see #released()
 	 */
 	public Connection getConnection() {
-		Assert.notNull(this.currentConnection, "Active Connection is required");
+		Assert.state(this.currentConnection != null, "Active Connection is required");
 		return this.currentConnection;
 	}
 

spring-web/src/main/java/org/springframework/http/converter/xml/MarshallingHttpMessageConverter.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2022 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -121,7 +121,7 @@ protected boolean supports(Class<?> clazz) {
 
 	@Override
 	protected Object readFromSource(Class<?> clazz, HttpHeaders headers, Source source) throws Exception {
-		Assert.notNull(this.unmarshaller, "Property 'unmarshaller' is required");
+		Assert.state(this.unmarshaller != null, "Property 'unmarshaller' is required");
 		Object result = this.unmarshaller.unmarshal(source);
 		if (!clazz.isInstance(result)) {
 			throw new TypeMismatchException(result, clazz);
@@ -131,7 +131,7 @@ protected Object readFromSource(Class<?> clazz, HttpHeaders headers, Source sour
 
 	@Override
 	protected void writeToResult(Object o, HttpHeaders headers, Result result) throws Exception {
-		Assert.notNull(this.marshaller, "Property 'marshaller' is required");
+		Assert.state(this.marshaller != null, "Property 'marshaller' is required");
 		this.marshaller.marshal(o, result);
 	}
 

spring-web/src/main/java/org/springframework/http/server/reactive/JettyHttpHandlerAdapter.java

@@ -59,7 +59,7 @@ public JettyHttpHandlerAdapter(HttpHandler httpHandler) {
 	protected ServletServerHttpRequest createRequest(HttpServletRequest request, AsyncContext context)
 			throws IOException, URISyntaxException {
 
-		Assert.notNull(getServletPath(), "Servlet path is not initialized");
+		Assert.state(getServletPath() != null, "Servlet path is not initialized");
 		return new JettyServerHttpRequest(
 				request, context, getServletPath(), getDataBufferFactory(), getBufferSize());
 	}

spring-web/src/main/java/org/springframework/http/server/reactive/ServletHttpHandlerAdapter.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2021 the original author or authors.
+ * Copyright 2002-2022 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -200,7 +200,7 @@ public void service(ServletRequest request, ServletResponse response) throws Ser
 	protected ServletServerHttpRequest createRequest(HttpServletRequest request, AsyncContext context)
 			throws IOException, URISyntaxException {
 
-		Assert.notNull(this.servletPath, "Servlet path is not initialized");
+		Assert.state(this.servletPath != null, "Servlet path is not initialized");
 		return new ServletServerHttpRequest(
 				request, context, this.servletPath, getDataBufferFactory(), getBufferSize());
 	}

spring-web/src/main/java/org/springframework/http/server/reactive/TomcatHttpHandlerAdapter.java

@@ -67,7 +67,7 @@ public TomcatHttpHandlerAdapter(HttpHandler httpHandler) {
 	protected ServletServerHttpRequest createRequest(HttpServletRequest request, AsyncContext asyncContext)
 			throws IOException, URISyntaxException {
 
-		Assert.notNull(getServletPath(), "Servlet path is not initialized");
+		Assert.state(getServletPath() != null, "Servlet path is not initialized");
 		return new TomcatServerHttpRequest(
 				request, asyncContext, getServletPath(), getDataBufferFactory(), getBufferSize());
 	}

spring-web/src/main/java/org/springframework/web/context/request/async/StandardServletAsyncWebRequest.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2021 the original author or authors.
+ * Copyright 2002-2022 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -128,7 +128,7 @@ public void startAsync() {
 
 	@Override
 	public void dispatch() {
-		Assert.notNull(this.asyncContext, "Cannot dispatch without an AsyncContext");
+		Assert.state(this.asyncContext != null, "Cannot dispatch without an AsyncContext");
 		this.asyncContext.dispatch();
 	}
 

spring-web/src/main/java/org/springframework/web/server/adapter/AbstractReactiveWebInitializer.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2021 the original author or authors.
+ * Copyright 2002-2022 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -28,6 +28,8 @@
 import org.springframework.http.server.reactive.HttpHandler;
 import org.springframework.http.server.reactive.ServletHttpHandlerAdapter;
 import org.springframework.util.Assert;
+import org.springframework.util.ObjectUtils;
+import org.springframework.util.StringUtils;
 import org.springframework.web.WebApplicationInitializer;
 
 /**
@@ -55,10 +57,10 @@ public abstract class AbstractReactiveWebInitializer implements WebApplicationIn
 	@Override
 	public void onStartup(ServletContext servletContext) throws ServletException {
 		String servletName = getServletName();
-		Assert.hasLength(servletName, "getServletName() must not return null or empty");
+		Assert.state(StringUtils.hasLength(servletName), "getServletName() must not return null or empty");
 
 		ApplicationContext applicationContext = createApplicationContext();
-		Assert.notNull(applicationContext, "createApplicationContext() must not return null");
+		Assert.state(applicationContext != null, "createApplicationContext() must not return null");
 
 		refreshApplicationContext(applicationContext);
 		registerCloseListener(servletContext, applicationContext);
@@ -92,7 +94,7 @@ protected String getServletName() {
 	protected ApplicationContext createApplicationContext() {
 		AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
 		Class<?>[] configClasses = getConfigClasses();
-		Assert.notEmpty(configClasses, "No Spring configuration provided through getConfigClasses()");
+		Assert.state(!ObjectUtils.isEmpty(configClasses), "No Spring configuration provided through getConfigClasses()");
 		context.register(configClasses);
 		return context;
 	}